This application is for a renewal of a training grant entitled "Basic Research in Hematology and Oncology," for the 16-20 fund years. The main goal of this grant is to train physicians whose primary discipline is hematology/oncology and prepare them for careers in biomedical research. The trainees are drawn primarily from M.D.'s who have completed clinical training in hem/onc following their clinical training in internal medicine or pediatrics. In some instances, trainees are drawn from pathology and neonatology or from other physician trainees who are interested in pursuing research careers. Ph.D.'s who show strong interest in the areas of biomedical sciences and are also occasionally accepted into this program. Since the inception of this program, there have been 31 trainees, of which 29 are M.D.'s or M.D./Ph.D.'s. Of the 24 who have completed training, 13 are full-time members at medical schools or teaching hospitals and 6 are practicing hematologists or oncologists. Others have pursued careers in biotech industry, competed for funding to pursue their research interests, or pursued residency training after completing the program. The faculty advisors are drawn from the Departments of Medicine, Laboratory Medicine, Microbiology/Immunology, Pediatrics, Pathology, Biochemistry, and Cellular and Biochemical Pharmacology. Their research interests cover the molecular genetics of hemoglobin production, control of differentiation of hematopoietic systems, gene transfer of hematopoietic cells, position cloning of genes affected by disease, the role of coagulation factors and vitronectin receptors in tumor metastasis, the role of oncogenes in the generation of hematopoietic disorders, the myeloproliferative syndrome and gene mutation that occur in leukemia, hematological signaling mechanisms, megakaryocyte development, virology covers the several important human viruses, functions of the T-antigen receptor, and defining the surface of GR and related receptors. The program, thus, offers a wide field of training choices in hematology, oncology, immunology, virology and genetics. In addition, three graduate programs, the Program in Biological Sciences, the Program in Biomedical Sciences, and the Molecular Medicine Training Program further enrich the training environment for postdoctoral trainees.